Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 | Page 5

the tests
to which they would be subjected.
"Inasmuch as the conditions and tests described in this letter were
subsequently followed in testing the explosives given in the list below,
they are here reproduced, as follows:
"(1) The manufacturer is to furnish 100 pounds of each explosive
which he desires to have tested; he is to be responsible for the care,
handling, and delivery of this material at the testing station on the
United States arsenal grounds, Fortieth and Butler streets, Pittsburg, Pa.,
at the time the explosive is to be tested; and he is to have a
representative present during the tests, who will be responsible for the
handling of the packages containing the explosives until they are
opened for testing.
"(2) No one is to be present at or to participate in these tests except the
necessary government officers at the testing station, their assistants,
and the representative of the manufacturer of the explosives to be
tested.
"(3) The tests will be made in the order of the receipt of the
applications for them, provided the necessary quantity of the explosive
is delivered at the plant by the time assigned, of which due notice will
be given by the Geological Survey.
"(4) Preference will be given to the testing of explosives that are now
being manufactured and that are in that sense already on the market. No
test will be made of any new explosive which is not now being
manufactured and marketed, until all explosives now on the market that
may be offered for testing have been tested.
"(5) A list of the explosives which pass certain requirements
satisfactorily will be furnished to the state mine inspectors, and will be
made public in such further manner as may be considered desirable.

"TEST REQUIREMENTS FOR EXPLOSIVES.
"The tests will be made by the engineers of the United States
Explosives Testing Station at Pittsburg, Pa., in gas and dust gallery No.
1. The charge of explosive to be fired in tests 1, 2, and 3 shall be equal
in disruptive power to one-half pound (227 grams) of 40 per cent.
nitroglycerin dynamite in its original wrapper, of the following
formula:
Nitroglycerin 40 Nitrate of sodium 44 Wood pulp 15 Calcium
carbonate 1 --- 100
"Each charge shall be fired with an electric fuse of sufficient power to
completely detonate or explode the charge, as recommended by the
manufacturer. The explosive must be in such condition that the
chemical and physical tests do not show any unfavorable results. The
explosives in which the charge used is less than 100 grams (0.22 pound)
will be weighed in tinfoil without the original wrapper.
"The dust used in tests 2, 3, and 4 will be of the same degree of
fineness and taken from one mine.[6]
[Footnote 6: With a view to obtaining a dust of uniform purity and
inflammability.]
"TEST 1.--Ten shots with the charge as described above, in its original
wrapper, shall be fired, each with 1 pound of clay tamping, at a gallery
temperature of 77° F., into a mixture of gas and air containing 8 per
cent. of methane and ethane. An explosive will pass this test if all ten
shots fail to ignite the mixture.
"TEST 2.--Ten shots with charge as previously noted, in its original
wrapper, shall be fired, each with 1 pound of clay tamping at a gallery
temperature of 77° F., into a mixture of gas and air containing 4 per
cent. of methane and ethane and 20 pounds of bituminous coal dust, 18
pounds of which is to be placed on shelves laterally arranged along the
first 20 feet of the gallery, and 2 pounds to be placed near the inlet of
the mixing system in such a manner that all or part of it will be

suspended in the first division of the gallery. An explosive will pass
this test if all ten shots fail to ignite the mixture.
"TEST 3.--Ten shots with charge as previously noted, in its original
wrapper, shall be fired, each with 1 pound of clay tamping at a gallery
temperature of 77° F., into 40 pounds of bituminous coal dust, 20
pounds of which is to be distributed uniformly on a horse placed in
front of the cannon and 20 pounds placed on side shelves in sections 4,
5, and 6. An explosive will pass this test if all ten shots fail to ignite the
mixture.
"TEST 4.--A limit charge will be determined within 25 grams by firing
charges in their original wrappers, untamped, at a gallery temperature
of 77° F., into a mixture of gas and air containing 4 per cent. of
methane and ethane and 20 pounds of bituminous coal dust, to be
arranged in the same manner as in test 2. This limit charge is to be